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FILE NAME: &'ZZ&' DATE: DOC#: &' DOCUMENT DESCRIPTION:d:ZZZD Lpmpounding Materi is User:; in the u ber I ustry Part II--Dry Inorganic Substances; Gums, Oils, Resinous Materials and Waxes; Liquids and Gases Industrial Safety Series No. RU-3 Published by the National Safety Council 20 North Wacker Drive, Chicago 1. This pamphlet is the second ift a series of two 00 "Compounding Material. Csed in the Rubber Indus- try first pamphlet, No. RC-1, confined to the classification of or- ,;anic accelerator,, anti-oxidants and dry organic compounds. This pain- confined to the following three groups of compounding mate- rials: \ 111(11..,,:.1111t. sllh ,1.111k ( unt ,d., resinous materials and s s Liquids and gases 2. An attempt has been made to 11 ,1 herein alphabetically, in the three above groups, practically all of the usual compounding ingredients used in the manufacture 01 rubber which are not covered in l'ainphlet No. kV-1. It should be realized, howc\ et-, that new compounding ingredient, arc constantly being developed and in some cases new and unusual .:,e, are bring made of the present algredient , A brief description of each compounding ingredient is giv. 11, together with it, use in the rubfer indo,trv, its relative health hazaid, :Ind recommendations for its -.ale handling from a health view .olut. Many of the solvents used in ,finpounding rubber ale flammable, (limn id the dry substances used (111',1 explosion hazard, and of various oils involves the ,L ik .,,or of ,spontaneou;, ignition. I ioN%e \ cr. the lire hazard, of the sub-:mice, listed are not discussed in de,: 1, a< those hazards are fully coveted in other publications. This pamphlet is a compilation of expezienee in accident prevention. It should not be assumed, however, that it includes every acceptable procedure in the field covered, It must not he confused with federal, state or insurance requirements, or with American Standard safety codes. Dry Inorganic Compounds 3. Alost of the compounds in this group are of a soft mineral powder type, of a particle size less than two hundred mesh, many of less than three hundred mesh, or liner. Few of them contain hard or abrasive particles such as silica or corundum. Only a few are toxic. On the whole they are comparatively free from health hazards. However, they arc all more or less dusty when handled carele,,ly, and the ordinary dust hazard is always present. Good storage bins, conveyor., hooded mills, and efficient exhaust systems will readily, eliminate the dust hazards and in most cases prevent harm from the toxic or silica-hem- mg compounds. (See also National safety Council -Health Practice, Pamphlet \o. 4, Dust," and Safe Practice., Pamphlet, No. 32, "FAhallSt and No. d4, "Re.piratory Protective Equipment.") 4. There are se\ eral compounds, however, that should receive special consideration, such as lead or silicabearing compounds. These ale so designated in the following list of materials. opyrwhi, /03.f, Nalional .1/I Aluminum Flake 3. A fine cream-tolortd p:psder, consisting primarily of 010100100: sill cats', used as a filler in railer. is non-gritty and f1(10-:oxit but rather dusty in handling. Ammonium Carbonate A white crystaline powder having a pungeut utior of am monia. It readily decomifo,e, ant give, off an irritating o.to. dunng mixing. It is used in sp. nge rt. fln.r, It is slightly toxic, but the-e health hazard as it is the rubber industry. Antimony Sulphides 7. There are two type:, file goinen and the red antimony used for coloring robber article, Some grades contain a considerable percentage of free sulphur ami tits)) sulphate. They at ...tightly ioxic, irritating to the ski:. and the mucous membrane- Care: u; handling is required. (See also Indusirlal Data Sheet D-Chein. 27. "Araulloro 01,1 Its Compounds ") Asbestine magn,,;ni r . silicate used iu rubhci as a dile; especially in paci.ings and gasket, It is t 110 \ t". non-grit t ao Mild-ioxic. It ,noald bo - ne iii mind, however. taut many of stlicate, when not ,sure, gnat' cornah. traces o: silica. and dust snot.al kept down. l'rlh"hill A ": INDUSTRIAL SAFETY SERIES NO. RU-3 (t tio-ous magnesium silicate used in many types of rubber goods, especially the packing and gasket. yne. and where the rubber must di-.'and considerable heat. It may in niaf V lengths of fiber, an inch lung to almost a pow- , an,1 .s usually gra\ Ish white in .'iearance Suitable exhaust ',vs- re,pirane protective equip- ,,ent are usually needed to prevent he inhalation of dust by the workers. ri um 1)tist (1. .\ trade name for barium sill, e. 11..trium Sulphate 1 \ heavy white powder used no. tenforcing rubber and also as a . ;ler It is insoluble in most sol\ ems it non-absorbable and non- , There is no hazard in handling, le iron: that of (lust. `rtes ' Commercial name for natural imrium sulphate. l'e,l,;(o n White 'wale name for lithopone. Bentonite is a The colloidal irom natural deposits. consisis (0. it tine grayish-white in many character- wh," C l s 14snionite, r, has ilc peculiar property of \ hydrolysing when brought in- coniiat with water and swelling ielly-like structure. Small ,tmoueis cause a I reIllelld01.1S thick- .alivi water solutions. On ac- count of these properties it is used as it !hickening agent and stabilizer 'or water dispersions of rubber. Because :Is activity and absorptive when brought into con- ii.(1 with water, care should he taken 1 ,1 event inhalation or swiallowmg the inst Blanc \ irrine.for precipitated win se ..late, ItI ue Lead A grayish-blue powder used .6 a mil(' acceltrittor and for coin- pemnling \ \tor( of active !cad ,-.,:sal'ound., aind vciv lo\ic (See lead Cadmium Yellow 17. A line light-yellow powder of cadmium sulphide, used for coloring rubber. It is slightly toxic. It can cause irritation of mucous membranes and also gastritis. Careful handling is required; hands must be kept clean and dust at a minimum in the workplace. Calcined Mtignesia 1S. (See magnesium oxide.) Calcium Chloride 0, whit e t o brown ish deliques- cent crystals or lumps which ate easil l' soluble in water. This material is not added to the rubber, but is dissolved in water and used as a bath for vulcanizing rubber articles. It is irritating to the skin but non-toxic. Carbon Black 20. An exceedingly fine dusty black powder. It is used in quantities for tires and many lines of rubber goods as a reinforcing ingredient. The dust is difficult to cope with but is non-toxic. Carbonate of Ammonia 21. (Sec ammonium carbonate.) Carbonate of Magnesia 7 2. (See magnesium carbonat('.) Caustic Soda 23. Same as sodium hydroxide. It is a white moisture absorbent substance, usually in the loan of sticks, flakes or lumps, and easily soluble in water. It is used as a bath or wash for rubber articles to cleanse, remove bloom, and gt ease. It is very caustic, disintegrates organic tissue, and should be handled with great care to keep it Inim contact with the skin and eves. (See also National Safety Council Safe Practices Pamphlet No. 25, "Acids and Caustics," and Industrial Data Sheet I)-('hem. 2, "Handling Caustic Soda.") Chalk 24. (See whiting.) China Clays 25. (See clays.) Chrome Green 26. A green mineral powder used for coloring ruldter. The most satisfactory gt eon for robber work is the oxide CO) which is inert and non- toxic. There are, however, so-called "chrome greens," which arc not pure chromium oxide but are mixtures of blue and yellow pigments made up of compounds other than chromium. Such pigments might have toxic properties, especially if they contain lead salts, Such greens arc usually unsatisfactory for heat vulcanization of tubber, since they lose their color under high temperatures. Nevertheless, the purity of chrome green should be determined before giving it a clean "bill of health." Chrome Yellow 2 7 . A deep-yellow powder used for coloring rubber. This is a eliminate of lead, although there are also chromaies of zinc and barium. The lead salt is the one usually used for rubber and is quite toxic because of the lead it contains. It should be handled with the same precautions as other lead compounds. (See lead compounds.) Clays 28. There are innumerable clays, varying in colors and ranging from white to black. awe used for rubber compounding are usually the white variety, ranging from white to cream or buff. 'AIost of the cl ay, are fine smooth powders, varying greatly in both chemical and physical properties. They are of natural origin and chemically a hydrous aluminum silicate. They are used as fillers and for reinforcing. The clays are usually non-gritty and mm-toxic. A suitable exhaust system or respirator is usually required to protect the resph atory organs. Crimson Antimony 29. Another name for red antim(Iny sulphide. I)iatomaceous Earth (Celite) A soft earthy rock composed of the siliceous skeletons of small aquatic plants called diatoms It winds to a fine powder, extremely light and fluffy, used for filler in rubber compounds. It is non-toxic, but care should be taken to keep clown excessive dust. A suitable exhaust syst em or re;pirat or may IA, Emery .11. .\ fine abrasive powder used with rabbet for making misers and COM I'OUNDING MATERIALS IN THE RUPPER INDUSY'Rr- PART 11 ,,.n. AN beck Basically. it is an oxide. It is non-toxic but sharp and dangerous to inhale. In us use the same precautions as for silica 'are required. (:\lso called corundum.) Fossil Flour 32. (Sec diatomaceous earth.) French Chalk 33. (See talc.) Fuller's Earth 34. A clay relatively high in magnesia. It is used as a filler in rubber goods and is non-gritty and non-toxic. (See also clays.) Golden Antimony 35. tSee antimony sulphides.) Gi aphite 36. A grayish-black soil greasy powder. Used for lubricating rubber moulds and as a filling material for such compounds as gaskets, packings, etc. It is an impure form of native carbon and is also produced artificially. It is non-toxic, but respiratory protection is usually necessary in its use. Ground Glass ;7. .\ tine powdered glass used for compounding rubber to make erasers and other rubber abrasive utensils The same precautions should lie observed as for silica. It is non- \ i c but shou ld not be handled with hare hands because it may cause minute skin lacerations that may become infected. Gypsum 33. .\ grayish-Ns bite powder used for compounding rubber. It consists of a pulverized natural hydrous calcium sulphate. It is non-gritty and non-toxic, but respiratory protection is necessary in its use. !lard Rubber Dust 30. A line ground hard rubber, grayish to black in color, very light and fluffy, and stick, to whatever it touches. Ordinarily it consists mostly of vulcanized hard rul)her, which is rubber and sulphur, hut it may also contain other mineral or organic substances used in compounding rubber, ilust should be kept down, but the material is not toxic. Finely ground rubber dust is explosive when mixed with air. I heavy Magnesia 40. Heavy calcined magnesia, or magnesium oxide. (See magnesium ON. de.) Hypo 41. Lead hypo-sulphite. (See lead compounds.) Iron Oxide 42. The red oxide of iron. (See red oxide.) Infusorial Earth 43. (Sec diatomaceous earth.) Kaolin 44. A clays.) china clay. (See Kicselguhr 45. (Sec diatomaceous earth.) Light Magnesia Oxide 46. The light calcined magnesium oxide. (See magnesium oxide.) Note; :\lagnesium carbonate is often spoken of incorrectly as light magnesia. Lamp Black 47. A black carbon pigment ohtamed by burning oils and oily residues. Carbon black is, often miscalled "lamp-black." Its characteristics are similar to carbon black (see carbon black). It is not used to any great extent. It is not toxic. Lead Compounds 48. Before the advent or organic accelerators, the lead compounds were the most. widely used accelerators of vulcanization. Some are still used in large quantities. The usual lead compounds used in rubber compounding are: Blue lead, lead thiosulphate, hyposulphite or hypo, lead ideate, lead oxide or litharge, sublimed white lead, and basic white lead. Blue lead, lead thiosulphate, and hypo are no longer used to any great extent. There are active compounds of lead which react readily with sulphur at vulcanizing temperatures to speed up \ 1.11CalliA411 i011. They are more or less active compounds and Ore readily assimilated if taken into the system, either through breathing or through food contaminated by contact with dirty hands or clothing. Lcad lode is still used to considerable extent bout a On tc celerator and for extruded and moulded goods. It g:ves a good finish and eliminates bloom in certain types of stocks. It is an active poison and should he treated with care. It is a soft, waky suostance, and so there is no danger of dust, the real danger being from sticking to hands and clothing. It can be handled with safety if cleanline,s is carefully observed. .50. Lad oxidc or lith.trge is proi-k. ably the most extensively used lead compound and the one most to l;c: feared. It is an orange-to-browncolored powder. The dust is ye, tine, but being heavy, settles quickly. Those handling this material should wear suitable respiratory protective equipment if there is the slightest danger of inhaling any (lust or getting dust in the moth h or saliva. It is dangerous to haifille tobacco, guin, fruit or any food until after the halals and face have been thorougnly washed. Mixing mills should I-K. hooded and every precaution taken to keep down dust. Lead oxide is toxic, but there is no need to enlarge here on lead poisoning. Litharge can be safely handled if reasonable cafe is exercised in its use. The worker should he instructed as to its serious toxic properties, and pains shout(' lie taken to show him how to handle it safely. 51. Sublimed 7.111.1e, !rad is largely lead sulphate with about 15 per cent of active lead oxide present. It is the bee lead oxide which is the active accelerating ingredient and also the real toxic substance. While much less toxic than the li;harge, should he handled with the same care as the latter sub. tance. 52. Basic -.did(' lead is a white powder consisting ctf a basic carbonate Of lead. It is not used now to any great extent for rubber compounding; but it is a very active and toxic substance and is used should be handled with as much care Os lit hai ge. 53. All persons using lead compounds to any extent_ should inform themselves on the s\ inptoms of 'lead poisoning, its treatment, and avoidance of trouble from poisoning. :*)ce National Safety C.ouncil i:ectith Practices Pamphlet No. 3, -l_tdd.") COMPOUNDING MATERIALS IN 7'11E R1'IWER I ND(IS7R1' A'7' II brown or gra\ ish. This is the material which has been so widely discussed in cases of silicosis. It occurs as an impurity in many dusts and powders and is usually present in common road dust. In rubber compounding, its use is confined to such special rubber articles as erasers and abrasive wheels. A very fine grade is also used as a filler for certain rubber goods. Wherever it is used, the workers weighing and mixing should be protected by exhaust system., or they should wear suitable respiratory protective equipment. There is an abundance of data available on silicosis which should be ,tudied by anyone using or contemplating use of silicon dioxide. (See also National Safety Council Health Practices Pamphlet No. 20, "Silicosis.") Slate Flour 73. .\ fine bluish-gray powder consisting of ground slate. In composition it is a sedimentary rock. It is used as a cheap filler and for certain heat-resisting and acid-resisting rubber goods. It is non-toxic, but it may contain silica; therefore precautions should be taken to prevent inhalation of the dust. Soapstone 76 ( See talc.) Sulphur 77. A pure natural deposit ground to an exceedingly fine powder. It is light yellow in color and is the principal vulcanizing ingredient used in rubber manufacture. With few exceptions, all rubber goods are cured or vulcanized with sulphur or with sulphur compounds. Sulphur dust is irritating to the eyes. respiratory organ, and skin. Gloves and shirts with sleeves may he necessary to protect the hands and arms. Goggles and respirators should be used if were i' much sulphur dust. Adequate ventilation and exhaust equipment should he provided to keep the dust at a minimum. There arc several varieties of sulphur, such as flower, of sulphur and ia-ecipitated sulphur, but chemically they are the ,,1111C t. the natural product. Talc 78. \ line white- to-gray powder that I eels extremely soft and peculiar- ly greasy or soapy. It is used throughout the rubber industry as a lubricant or dusting powder. It is a hydrous magnesium silicate, very inert. It is non-toxic, and there is no health danger in its handling other than that of dust. Tellurium 79. Tellurium is used to a limited extent as a vulcanizing agent and especially where very low-sulphur stocks are desired. It is a grayishblack amorphous powder. Definite records as to its toxicity are lacking, but some workers appear to 1);` very sensitive to the odor given off when they come into intimate contact with rubber stocks containing this chemical. Aside from the disagreeable odor, there appear to be no records of cases where it has presented a serious health hazard when used in rubber. It is advisable to protect workers from direct contact with the material as much as possible. Titanium Dioxide 80. Titanium dioxide, either as the oxide or in combination with barium or calcium sulphate, is used as a white coloring pigment for compounding rul,ber. It is one of the whitest and most stable of the few white pigments suitable for rubber. These titanium whites are exceedingly fine while powders, and the usual precautions for pigment dusts should be observed. There appear to he no records of their having caused any toxic hazards as used for rubber compounding. Tripoli Si. Also called rotten stone. It is a porous, siliceous rock resulting from the natural decomposition of sandstone. It is used as an inert filler and as a mild polishing compound for rubber. It is non-toxic, but care should he exercised to 1)i-event excessive dust, and especially inhalation of dust, since it may contain a small amount of silica as an impurity. Tripolite 82. (see diatomaceous earth.) Ultramarine Blue 83. A powder used for coloring rubber goods. Its composition is variable but consists essentially of a dou- bit silicate of :-.();iiihn and aluminum. and sodium sulphide. It is a darkblue powder, itt4 to heat and sulphur. It is non-toxic, but dust should be kept to a minimum. Umber 84. An iron oxide with varying amounts of day and silicon com- pounds. There are two common va- rieties. The raW umber is the nat- ural deposit ground and made smooth, whereas the burnt umber is calcined at low heal. The former is a Yellow- ish-buff to brown color, and the latter a reddish-brown color. They are low cost colors, used extensively in rubber floorings and mechanical goods. There is no health hazard in their handling other than that of the dust. Venetian Red 85. (See red ox;de.) Vermilion 86. A fine brilliant scarlet-toorange-colored powder consisting of mercuric sulphide. It is used in a limited way for coloring certain types of rubber but is too costly for general use. It is a very inert compound, and no health hazard is involved in its use except that of dust. Whiting 87. A soft white or gray powder consisting or more than 98 per cent calcium carbonate. It is one of the most widely used filling compounds for rubber manufacture. The poorer grades n-ty contain some traces of silica. It is non-toxic, and there is no health hazard connected with its use unless it con'.ains free silica, which can he determined by laboratory analysis. White Lead 88. (See lead compounds.) Yellow Wm: 89. A mineral deposit wit:en, when ground, prod(.tccs a cheap Pigment used in coloring rubber goods. Used principally for flooring and mechanical goods. It con,Lts, of hydrated ferric ov,de mixed with clay and other silicon!, material, in varying amounts. Into is no health hazard in its use except that of dust. Zinc Oxide 90. Next to sulphur, this is piol, ably the most wi6ely used rubber INDUSTRI:II,,S":1FETY SERIES NO. RU-3 Lime 54. 'A fine dry white powder used extensively in rubber compounding as a secondary accelerator and drying ingredient. This compound is the so-called hydrated calcium oxide or slaked lime. It is slightly caustic and irritating to mucous membranes, and suitable protection against its caustic action is required. (See Industrial Data Sheet 1)-Chew. 19, "Lime," for details.) Litharge 55. Lead oxide. (See lead compounds.) Li thopone 56. A line white powder consisting of barium sulphate and zinc sulphide of high coloring power. It is a widely used pigment for producing white rubber goods. Being rather inert, there is no hazard con!laded with its use other than the general dust hazard. The zinc present in the material might be dissolved if considerable quantities of (lust were taken into the system, but zinc in such small quantities would not be considered as a toxic material. Magnesium Carbonate 57. Also called magnesia carbonate and light carbonate. This is a fluffy white powder; next to carbon black it is one of the lightest powders used, and it therefore causes considerable dust. It is very soluble if taken internally, but it has no poisonous effects. It is an ingredient often used for baby and toilet powders and also used in man medical preparations as an anti-acid and mild laxative. There is no health hazard connected with its use other than that of (lust. Magnesium Oxide 5S. Also called magnesia oxide ,u,(1 calcined magnesia. It is obtained by heating the magnesium carbonate. TN\ 0 grades are used extensively in the tubber industry, one called heavy calcined magnesia and the other light calcined magnesia. The heavy product is inure dense and slightly darker in color than the light calcined material. Both are used as auxiliary accelerators and to neutralize acid reactions. The percentage used is relatively small in most cases. The dust is slightly irritating to mucous membranes but non-toxic. Suitable respiratory protection is required in its use. Magnesia Usta 59. Same as magnesium oxide. Mica 60. A form of aluminum silicate which, when finely ground, is a soft glistening powder. The flat particles slide over each other, giving the slippery properties noted in graphite. The color runs from a cream white to gray. It is used for dusting raw rubber to keep the slabs from sticking together, also for dusting finished goods to give a smooth, glistening finish. Mica is also used in packings and mechanical goods as a filler where goods are to resist heat and acid. The material is non-toxic, and there is no hazard other than the dust hazard. Cheap grades, however, may contain traces of silica, Suitable respiratory protection is necessary. illicit in needle-like form is likely to be more irritating to the skin and nasal passages than mica in plate form. Oxide of Magnesia 61. (See magnesium oxide.) Oxide of Iron 62. (See red oxide.) Paris White 63. (See whiting.) Plaster of Paris 64. (See gypsum.) Plumbago 65. (See graphite.) Pumice 66. A grayish powder consisting of ground lava. It is a complex silicate of aluminum, potassium and sodium. lt is used as a soli abrasive for producing a smooth polished surface on rubber goods such as mechanicals and rolls. Also it is used as a tiller in acid and heat-resisting robber goods. It is non-toxic, but care should be exercised in keeping down dust. Prussian Blue 67. There are a number of so- called prussian blues with varying shades and solubilities, all belonging to the iron blues. They are ferroferri-cyanide compositions and arc non-toxic. The blues used for rubber are the insoluble type and prepared to withstand the temperatures of vulcanization. They are used in comparatively small quantities, and . there is no health hazard connected with their hapdling, aside from that of dust. Red Oxide 68. A fine red pigment, very dense and heavy, and consisting of the red oxide of iron; also called iron red. It is one of the most widely used red pigments for coloring rubber. It is non-toxic, and no serious health danger is involved in its handling. However, it is advisable to keep dust down, as the oxide flies readily. Red Ochre 69. A (lull brownish-red powder used for coloring rubber goods. It consists of a ground natural impure form of iron oxide, more gritty as a rule than the regular red oxide. It is non-toxic, but it may contain silica, and so care should he exercised in keeping down dust. Rotten Stone 70. (See tripoli.) Sand 71. (See silicon clioxicie.) Selenium 72. Metallic selenium in the form of a fine heavy grayish-black powdcr is used to a limited extent in several branches of the rubber industry, notably in the insulated wire industry and where a very low percentage of sulphur must be used. Information concerning its toxic properties is rather meagre. It is claimed to he non-toxic, and, we have no records to indicate that there are any health hazards in connection with its use in the rubber iadustry. It is advisable to protect workers a.oin-t in halation or swallowing of th, dust. Silica 73. (See silicon dioxide.) Silicon Dioxide 74. Also called silica and quartz, sand, etc. A hard abrasive powder. varying in particle size from a very fine powder to large sharp parCeles known as sand. "1he color toss from almost pare white to yellow or ('OAIPOUNDI.VG 31.1TER1,ILS IN THE RUBBER INDUSTRY- P., IRT 11 7 Cottonseed Oil I It) A hale VedoW - to - reddish- n oil obtained from seeds of the -cotton plant. It is used in rubber as a softener, for reclaiming old rub- ber, and in conjunction with resins to produce tack. Cumar 111. A svnthetic resin consisting of polymers of coumarone, indene. and homologous compounds. lt can he obtained in several states, varying from a liquid to hard, high-melting resins. The color varies from lightbuff to brown. it is used quite exteleavely in various rubber compounds such as those for soIes, flooring, friction tapes and cements. Cumin- is also used in acid-resisting and alkali-resisting stocks. It is nontoxic. 1)cgras 112. Also known as sod oil and wool gi ease. II is a dark-brown grease obtained from the washings of sheep's wool. It is used as a softener and for aiding in the processing of raw rubber, such as in calendering and extruding. It is non-toxic. Factice, Black 113. A black gummy cake resembling rubber but easily disintegrated by crushing. It is made by vulcanizing vegetable oils with sulphur and adding mineral rubber. Black factice is added directly to the rubber on the mill and is used as a soft filler. It has the property of absorbing other fillers and thus hulking up the rubber. It is also used for producing a smooth finish on calendered and extruded goods. There is no health hazard in the use of fact ice. l'actice, lirc)wa 11.1 .\lso called brown substitute. It is a vulcanized oil usually made 0.11 or sitigiar hearing with sulphur chloride. Rapeseed in soya bean oils are often tied for making white factice. The factice is added directly to the rubber hatch on the mill. It k used in druggists' sundries, tubing, extruded articles, rolls, pads and moulded article-;. It gives a smooth, velvety finish and facilitates calendeling, tubing and other processing operations. There is no hazard aside from that of dust. Gilsonite 116. :\ very pure natural bitumen found in the Irnited States only. It is a black mass breaking with conchoidal fracture and showing bright lustre. It is used in flooring, mechanical goods, coatings, varnishes, insulation, gaskets and cements. Glucose 117. A thick, viscous, syrupy liquid made from corn. It is used in a few rubbe r compounds a n d cements, and for latex compounding. Glue and Gelatin 11S. A nitrogenous colloidal substance of the protein class which is derived f r o in animal connective tissues and bones obtained from slaughter house and tannery waste. It comes in sheets, chips or ground granules, usually of a light-amber color, and always contains some water. It is added directly to the rubber on the mill or dispersed in water. Glue is used in rubber as a reinforcing ingredient of low gravity. It gives strength, stiffness and good processing qualities. It is used in tubing, rollers, coatings and latex compounding. Guayule 119. A resinous rubber native to Mexico and southern United States, having about twenty-five per cent of resin. It is used largely for soft rubbers :-11(1-1 as friction stocks. Being of a soil I esinous nature. it doe Gum r gac 121. 1)1111 v, !lite Hanslia daises or yellowish powder. It is a vegetable gum used for cements and as a thickener for latex solutions. It is non-toxic. Gotta Percha 122. 'The coagulated milk juice of various tropical trees. It comes in yellowish or grayish hard leathery sticks. It is used with rubber to impart certain leathery properties and in golf ball manufacture and cements. (me large use has been in al.' coating and impregnation of fabric for driving belts, clutch lining, and wire coverings. It is non-toxic. Hardwood Pitch 12.1, A brown bituminous material consisting of the residue from the distillation of hard wood. It is used as an accelerator activator, and for giving tackines, to rubber stocks. It is added directly to the rubber on the mill. Oily comparatively small ppreenlage,, are used, and no health hazard is involved except that of possible skin irritation;. I Eydrolene 121. A black bituminous mass resembling asphalt, obtained from the residue remaining after the destructive distillation of petroleum. Used as a filler ant. softener in much the same manner as asphalt. (See asphalt.) Linseed Oil 125. An amber-colored (Irving oil obtained from the seeds of die 110x plant. it is used in roller, and cements in preparing rubber substllutes in the form of factice by vulcanizing the oil with sulphur chloride. It is non-toxic. Mineral Oils 126. Numerous grades of mineral oil, ranging from the light i )araffin I it, iv tio,1111!I ,I,e u-ed lor ocessei it Inc stdgc it n c,n.e. easily crumbled. the ralher en ra,2, It is useo as a soft fililng material in moulded goods, druggists' sundries, proofing and tubing. Factice, White 115. A white granular powder prepared by vulcanizing vegetable oils as smokt silt cu.-, and small amoai l , are often added to the harder rubber-, to spekd up the breaking dov.n thne. Gumkaraya 120. Gumkaraya is a bassora type of gum similar to gum tragacanth. It is used for thickening latex solutions and is non-toxic. .are 11.1.2 A ara :in c,i c di - on n-:;11 and rubber. Therc as no health hazard. except possibly that of skin irritataon. Rubber 127. A term applied to nat.,.,t1 asphaltic deposits such as glisunite /XDUS1R/.1/,,S',IFE7'1" SERIES NO. RU-3 ingredient. It is used both as an acteva(or of acceleration in vulcanizing the rubber and as a white reinforcing ingredient It is a fine white amorphous powder. Taken internally, it is slightly toxic, but with proper precautions for keeping down the dust there is no serious health hazard in its handling. however, many grades of zinc oxide contain lead salts which increase their toxicity. Zinc Sulphide 91. A fine white powder with yel- lowish tinge used for coloring rubber. It has gloat coloring power hut is not as good a reinforcing ingredient as zinc oxide. There is no especial hazard involved in its use. (See also zinc oxide.) Gums, Oils, Resinous Materials and Waxes 02. The substances in this group are largely used as softeners and plasticizers. 9.5 This group contains materials which are either liquids or semisolids, and therefore there is no dust hazard. Also, all members of this group are practically non-volatile at temperatures encountered in rubber processing. None of the substances mentioned is known to be toxic with the possible exception of some of the tars or pitches. They are not hazardous as used in the rubber industry because of the relatively small amounts used and because they are neither in fine particles nor sufficiently hot to give off fumes. 9-1. The oils are usually added directly to the rubber on the mills and worked in. The solid resins and waxes are either niched or ground to coarse flakes before they arc added to the robber: with s easonable care mot cleanliness there is .,a health hazard in their use. 95. ()ils and resins known as organic accelerators are not included with this group but are discussed in N. S. C. pamphlet No. RU-1. Asphalt 06. Also called bitumen and min- eral pitch. It is a natural deposit of bituminous mixture, either solid or send-solid, readily softened by heat, and is used as a softener and cheap filler, especially for extruding and covering stocks. The color of the natural materials is brown or brownish-black. Many treated or blown asphaltic compounds are also used in rubber compounding, and the latter may he obtained in almost any degree of hardness. They are usually black and have a bright fracture when broken. Asphalt handlers may be troubled with irritation of the skin because of the mineral oil in the asphalt. Therefore handling of asphalt with the hare hands should he avoided where possible. Balsam 97. (See Canada balsam.) Beeswax 95. A yellowish-to-white colored wax obtained from the honey comb of bees. it is tough and has a fairly high melting point. It is used to render rubber impervious, as well as a softener in extruding, and as a mild preservative against the action of light. Bitumen 99. (Sec asphalt.) Brown Substitute 100. (See factice, brown.) Black Substitute 101. (See factice, black.) Burgundy Pitch 102. An opaque yellowish to reddish-grown resin obtained from Norway spruce. Softens under heat and is used in conjunction with other oils, to give tack to rubber, especially unvulcanized frictions, tapes, etc. It is also used in tacky cements. Pitch is a skin irritant to many persons, especially when a high standard of personal hygiene is not maintained. Canada Balsam 103. A resinous exudation front spruce, used to give tack in rubber frictions and cements. (See also burgundy pitch.) Carnauba Wax 104. Kited quite extensively in rubber compounding to produce a dense, impervious product for lubber coatings, flooring, etc. It is a very hard, vell(mish-to-buff-colored wax of high melting point; it usually is melted before it is added to the rub- her hatch. Cal Haulm wax is obtained as an exudation iron leaveof the lliazilian wax pain:. Its use does not present any special hazards Castor Oil 105. A alit]. vellov,ish oil obtained front the castor bean. Used as a softener in rubber anti in the product1(01 of certain rubbe. substitutes or factice. Ccresin 109. A put lied mineral earth v.ax having a inelthhii point of approximately 7-I degrees Centigrade. It comes in \vhite cakes. Used in rubbet' to render it more impervious to water and air, as a softener, dnd extruded articles andcovffings, elee trical insulations and for acid-resisting rubbers. No hazard is involved in its use. Coal-Tar Pitch 107. A bro))n to-black amoriiilous body consisting of the residue remaining after the coal-tar has ;wen distilled. it varies from a soft stick) to a hard brittle mass according to the degree to which distillation ha-. been carried out. Coal-tar pita: is used as a softener and tack producer, and for extruded goods. It may cialtain residues of coal-tan products which arc toxic, but the high temperatures of distillation should remove most of these, and the smt.ii amounts used for most rubber work preeliaie any serious health hazard in use, provided a high standard of personal hygiene is maintained. Colophon), 10S. Coinmon -dine resin which is obtained as a residue after the dis- tillation of turpentine oil ;ram crude turpentine. Varies in colon from light-amber to dark reddish-in own. li it tied in rulther compound, ;a:- producing lack in r ii 1> h cement:s. It thualiv Conies in lunly and is readily pulverized or melts down when added to the ru!..ixe batch on the mill. There is no known hazard in its use. Corn Oil 109. A pale vellow oat obtainoo from the germ of corn. ft is the' bt rubber as a softener, in LeCi,th; old rubber, nrd in the tiltultif,a of factice or rubber substitute. INDI 1STRI/11, NAP F.TY SERIES NO. RU-3 and also to blown asphalts. lilown asphalts may be obtained in varying degrees of hardness and are sold acein ding to their respective melting points. They are often called ":\I. R." by rubber compounders. Mineral rubber is used in many lines of rubber manufacture both as a cheap bulking filler and to aid in processing raw rubber. It is used in frictions, spread goods, cements and many types of mechanical rubber goods. Alineral rubber comes as a solid mass in sheet metal drums or it may he obtained in a granular form. It is added directly to the rubber on mil; There is no health hazard ceresin which is prepared from ozokerite.) There is no health hazard. Palm Oil 132. An orange-yellow fatty oil or grease of hinter consistency. It is obtained from the fruit of a tropical palm. It consists chiefly of palmitin acid and the glycerides of palinitic, oleic and stearic acids. It is used in rubber to aid processing, especialv for producing a smooth finish on calendered and extruded goods. Also used to reduce the tack in very sticky compounds. There is no health hazard in its use. Paraffin Oils is usually added (Erectly to the rubber batch on the mill. Pine Tar Oil 137. A redOish-brown stM- , stance obtained from the destructive distillation of pine wood. ft is a lighter distillate than pine tar. It has a strong tarry oder nail taste. The material is somewhat toxic and should be handed carefully. It is used for the same purposes as pine tar in rubber, but the lighter oil is preferable for c_Ttain compounds. Rapeseed Oil 135 \ ).it c'hm crushing, and the liberation in by tirogen sulphide which should be removed by adequate ventilation. 1\lontan Wax 12S. A mineral wax extracted from lignites. In the crude state it is dark brown. When refined, it is a v.. lute v. :Ix. T he crude wax is used for soling, flooring, special stocks, insulating compounds and extruded stocks. This wax imparts excellent processing qualities without the soliciting effect resulting from the use of softer Nvaxes such as paraffin. No hazard in its use. Naphthalene 120. \\lite crystalline flaky compound, used to a limited extent in certain rubber goods as an odorant and processing aid The material has a camphor odor characteristic of moth halls. It may contain, as impurities, coal-tar products which are slightly toxic. However, such small quantities are used in rubber com'vaunting that the health hazard is slight. Oil Substitutes 130. (See factice.) Ozokerite 131. A mineral fossil \N ax occurring native, and yellowish-brown-toblack or green in color. Used as a rubber filler and softener. especially in such goods as electrical insulations, frictions, extruded and mechanical stocks. Usually added directly to the rubber on the mill, either as broken lumps or in molten state. (See also para u m \\ , a\. 134. A white, translucent, waxy, tasteless and odorless solid obtained from petroleum. It consists of a mixture of hydrocarbons chiefly of the methane series. It varies in color from the light-yellow crude to a hard white refined pax. Wax is used in rubber as a softener, as an aid to processing, as an anti-scorch material, and as an anti oxident and light resistor. It is also used for rendering rubber less permeable to water solutions. Petrolatum 135. Also called vaseline and mineral fat. A light-yellow-to-amber colored, oily, semi-solid material consisting chiefly of hydrocarbons of the methane and olefine series. It is obtained by distillation of the still residues obtained in steam distillation of paraffin base petroleum. It is used in rubber as a softener, in reclaiming old rubber, as an antiscorch inaterial for active accelerators, and to aid in smooth calendering and extruding operations. There is, no health hazard. Pine Tar 136. A very viscid, blackishbrown liquid with a chara c ter istic odor and taste. It is obtaiaed from the destructive distillation of pine wood. It is used in rubber goods as a softener, tack producer, dispersing agent, and at elerator for synthetic rubber. It finds a large use in tread stocks, frictions, tape, reclaiming of rubber and cements. It contains phenolic bodies, hut as used in rubber it should not be hazardous. It leaking takaat e dr subst itute. (See lattice.) .)i)L't Rosin 139. (Sec colophon:.) Ro,,in Oil 140. 11 alci,)c-r-col6r,.;' oil'' liquid, with it pleasant odor IA!l a scrong, peculiar taste. It is obtained by fractional dt-tillation of rosin. It is used for producing tack in rubber adhe!,ives, tapes, mcchanicak and in reclaiming lubber. Tncrc is no health hazard. Shellac 141. A resinous exudation from the twigs of a species of 11.;,st Indian tree; it is cawed to exude by the bite of an insect. It la obtained as orange-to-light-buff brittle flakes, or a ground powder. It is used to a limited extent in rubber as a stifft nee ;la in bard rubber to give iiinmess and finish. It is non-toxic. Sod Oil 1 12. (Sec degras ) Stearic Acid 143. .1 colorless, ociories, waxlike material handle 4 in block, o r (lakes, It is obtained ;;tea, highgrade beef ta.low,, by nr distillat.on anti pressure an( by hydrogenation of oleic ,aal. It is used in nio-t types (ef rdbl,c, goo d!, a', a stabilizer of vuican;,-,dion, a!-!!tri activator o! c!!riain !a celcratois, ,teal ;Is a dispersing agen! and -;:RentIt is u,c(i up to -e r 2: the rubber adal added tid,--tt:, COMPOUNDING MATERIALS IN TUE RI 11313ER INDUSTRY- PART II 9 r ubber. in which it readily disperses. It is-nun-toxic. 1 Liquids and Gases 144. In this group are included the usual liquid solvents and gases used in rubber manufacture with the exvtion of the liquid accelerators, which are listed under organic ac- celerators in N.S.C. pamphlet No, RL7,-1, and softening oils, which are listed above. 145. This group contains some of the most hazardous chemicals used in the industry and should be given careful study by the safety engineer to see that they are properly handled. Liquids Acetic Acid Ho. Acetic acid is not used generally throughout the rubber industry. only in special parts of it. It is, however, used in large quantities for certain purposes. It is used for coagulating rubber latex, in certain latex preparations, and in sponge rubber production. In coagulating and latex work, the temperatures are low or normal, comparatively small proportions on the batch arc used, and handling is simple. When used ior sponge rubber, the temperatures are higher, and disagreeable I utiles are given off which should be conducted away by proper ventilation and exhaust equipment. 147. Acetic acid is a clear, colorless liquid at ordinary temperatures. It conies in a number of different strengths, varying from the pure concentrated acid, known as glacial acetic acid. down to dilutions as low as 2s per cent. It has a strong, pungent odor characteristic of vinegar and is very corrosive, especially in the higher concentrations. It is very irritating to hands and nasal passages. In small quantities it is not toxic, but can. should be taken to keep it away nom the bare skin, and any fumes snould lie conducted away from the workers. Alcohol 14ti. Alcohol is usually used in the denatured state. Its use is not extensive in the rubber industry, bemg confined to certain types of cogent>. as a means of introducing certain resinous compounds into rubber, and as a cleaning solution for raw and finished rubber where it is necessary to avoid solvent action on the rubber. The characteristics of alcohol are \yell known; it is not necessary to dwell here upon its relative toxicity. Various types of denatured alcohol are available, and all are toxic if taken internally; but as used for rubber work there should be no hazard if not actually taken internally. All grades of alcohol are flammable. Ammon is 149. Ammonia is a (-Dim-less gas, but as usually used it is dissolved in water and known as ammonia water or ammonium hydroxide. It is sold on its ammonia content designated by degrees Baume. The usual grade used is 20 Baum', or a saturated solution. It is a clear, water-like liquid with a strong, irritating 0(101.. In the concentrated form it is strongly caustic and should be kept away from the skin. Rubber gloves and noti-venMated goggles should be used in handling it. it gives off powerful, pungent fumes when exposed to the air, causing bronchial disorders if inhaled in considerable quantities. The fumes are toxic. but usually do not leave any serious lasting effects, Where used, a good ventilating or exhaust system should be installed. In the more dilute forms of ammonia liquid, the water retains the gas in solution, and only slight fume; ale given off. Under certain conditions ammonia mixed with air is explosive. 150, Dilute ammonia is used very generally to preserve raw latex, in manufacturing latex compounds, and throughout the liquid latex industry. The concentrations here seldom run higher than a few per cent, and there is practically no hazard other than where the ammonia solutions are prepared. Ammonia is also used in the spread-goods industry as a neutralizer for acid released (luring the vulcanization o;Trat ion where sulphur chloride cures are used. The hazard here is also small since most of the cold curing chambers are of lie( esshy equipped with adequate venting systems. (See also N.S.('. pamphlet No. 25, "Acids and Caustics.") Benzoi 151. Ilenzol, or benzine, as it is chemically defined, is a clear, water- white liquid of characteristic odor, derived from the destructive distillation of coal. it is very volatile at room temperature, and should never be allowed to stand in open containers. The vapors ,ere very flananalile find very toxic. jlenzol is used largely for making cements and adhesives for assembling rubber parts during process of manufacture. It was formerly used in large quantities as a wash for raw rubber, being applied by hand swabs. ft was here that many of the most severe poisoning case; were expierenced. The vapors spread rapidly and should be removed by ellaust systems to decrease bath the tire hazard and the health hazard. The workers should not he allowed to breathe any considerable quantity of benzol vapors, nor should they lie permitted to get the solvent on their clothing, hands, or other parts of their bodies. The solvent can be absorbed through the skin Os well as through inhalation, producing lasting serious complications. (Sci' N.S.C. pamphlet No. H.P. 14, "Benzoi.") Benzene 152. Same as benzol. Must not he confused with benzine, which i, a petroleum product and not a coat-tar product. Benzine 153. A distillation product from petroleum, being a char solvent similar in properties to ordinary cleanei,' naphtha but very light and volatile. Also called petroleum ether. it i, used as a cleaning s( lvent for :,Wal)bing raw rubber am, is much safer to use than benzene, from the toxicity standpoint. I low ever, it is very flammable. It should be th-i'd In safety dispensers to eliminate the tire hazard. breathing benzine vapors will cause dizziness, Carbon li.nallphide 154. A clear, , very flam- mable liquid. When pure it is al- most odorleaa but the commercial grade usually used has a :.trong, dis- agreeable odor, It k exceeningiy volatile at room ICITipermorel, having a flash point at minas 25 degrees Centigrade. It may ignite from a spark or flame many fe,it away. It is very poisonous to bceathe. (For further details a, to it, to.xicity. N.s.C. Inclu,mal Data' Sheet u- Chem. I, "Carbon Iiisulphide.") INDVSTRI.II.S.IITTY St.:R/1'S NO. RU-3 155. Carbon bisulphide is used cot: temoving sulphur bloom on rub- goods, in rubber adhesives, and a, a diluent for sulphur chloride in cold vulcanization and vapor cure. Departments using this solvent should be adequately equipped with fire extinguishers and exhaust systems. Keep solvent off the hands. 156. Within recent years the use of carbon bisulphide has been very limited as, in the majority of cases, less dangerous materials have been substituted. There are, however, a lew places where it finds a use in rubber manufacture, and the safety engineer should study each situation and see that the material is handled in a safe manner. Carbon Dioxide 157. Carbon dioxide is an inert gas used in the rubber industry for inflating air bags and tubes and for vulcanizing purposes. It is non-toxic, but is highly suffocating since it is devoid of active oxygen and does not support life. Its danger lies in the fact that it is a heavy gas and likely to collect in -dead pockets" where ventilation is poor. Omsiderable quantities may be liberated through leaks. or discharge from bags or vulcanizers at the conclusion of vulcanization operations. Adequate ventilation will remove any danger. Carbon Tetrachloride 158. A light, colorless liquid with a peculiar characteristic odor. It has a low boiling point and is very volatile at room temperature, giving off heavy vapors. The vapors are not flammable but are toxic. They arc heavy and sink to low parts of the room, often collecting in corners and poorly ventilated places, making a real hazard to workers unless removed by proper ventilation or exhaust equipment. This solvent finds an extensive u,e in rubber manufacturing on account of its freedom from fire hazard and its excellent solvent properties for rubber. it has replaced many other solvents. (See N.S.C. Industrial Data Sheet 1)Chem. 25, "Carbon Tel Chloroform 15Q. A clear, colorless, highly volatile liquid with a peculiar characteristic odor. It is toxic, but it will not ignite readily. It is an excellent solvent for rubber and is used for cements and cleansing solvent. I lowever, it has been almost entirely replaced by carbon tetrachloride which has properties very similar to chloroform where used in rubber manufacturing. it should he handled with the same care as carbon tetrachloride. Coal-Tar Naphtha 160. Relined coal-tar naphtha is a clear, water-white liquid having a heavy, gasv odor. It is flammable and should be kept in approved dkpensers. There is also a crude material which is straw colored, but this grade is not used to the same extent as the refined grade. Coal-tar naphtha consists of a mixture of benzene, toluene, xylene and other higher homologs. It is toxic, but less volatile than henzol. It is used to a considerable extent for rubber cements, rubber (loughs, and as a cleaning solvent. The same precautions should be taken as for henzol. Ethylene Dichloride 161. A colorless liquid having a strong chloroform-like odor. It is an excellent solvent for rubber and is used for rubber cements and (loughs on account of its low fire hazard. It is toxic and in many respects acts like carbon tetrachloride. it should be handled in a similar manner to carbon tetrachloride. Its vapors are very heavy. Gasoline 162. The name given to it series of solvent distillates derived from petroleum and having a range in gravity from 50 degrees to 00 degrees liaume. The range front 56 degrees to 70 degrees is the usual range of rubber solvents. They are clear, water-white, oily liquids of characteristic not unpleasant odor. The gasolines are the most universally used solvents in rubber manufacture, partly because of their low cost. They are all toxic and flammable and should be handled with care. Vapors should be removed. Ga,oline dissolves the natural oils and fats of the skin, causing dry and happed skin. This can he prevented to a great extent by list coating the hands with a neutral glycerine soap preparation, which repels the gasoline. 1 n i. Gasoline is used as a cleaning and swabbing solution in the manufacture of many rubiaa. articles, in al: types of rubber cements. in preparing coating a n d spreading (loughs, and as a diluent for other solvents. Glycerine 164. Also called glycerol. it is a clear, colorles., or pale-yellow, heavy, syrupy and odoric-s liquid having a sweet taste. It is non-tlammable and non-toxic and presents no hazard from the health standpoint. It is used in rubber manufacturing as a preservative fating or dressing on finished rubber goods, to prevent rubber from sticking together while in the yaw state and in liquid latex preparations 1Vhen used as 0 dressing, it is either ..waldied, sprays(, nr painted on, Kerosene 165. A clear, watei - white to straw-colored, oily liquid. It is obtained as a disti:iate from petroleum and refined to remove low flash ,aituentk;. it is comparatively -.fie to use, although the skin 01 some workers is sensitive to kerosene nit It is used to a limited extent in rubber manufacture. but very extensively as a wash for rubber machinery, rubber rolls, etc In rulfber manufacturing it is used for softening aid blowing sponge gnml-s. Kerosene presents a tire hazard, but it is not as hazardous as gasoline Naphtha 166. A given to both 1>etro- letim and coal-tar solvents. The of naphtha should be otherwise it it very misletting. (For pet ndeum naphtha, see benzine. petroleum ether. and For coal-tar naphtha see coal-tar naph- tha.) Petroleum Ltber 167. thee benzine.) Solvent [Naphtha 168. (See coai-tar naphtna.f Sulphur Chloride 169. TIfi o; sulphur. It is an amber-to-yellowish-re;i. fuming liquid will very pettetra:InLt odor, used 10 vulcanizing r1,1),, the so-called cold process arc; t.. or process. Its ase as such is confined COMPOLVDIXG 411.ITER1.1 LS 1.1' 7 RI TIMER INDlisTRy 1,,IRT Ii 11 aigely to sheet, spread and dipped 11 is also used in the manu- facture of rubber substitutes and oil lattice. When used for sheet and '.preach goods, the sulphur chloride may be applied in liquid form by distributor roll, or the goods may be hung in chambers where the sulphur Idol hie is vapolized by heat. The sulphur chloride is extremely active chemically and is usually diluted with some solvent such as carbon bisulphide or benzol. In vulcanizing dipped goods, the latter are usually immersed for a very short time in a diluted solution of the sulphur chloride. 170. Sulphur chloride is readily decomposed in a damp atmosphere and should be kept well bottled when not in use. It is extremely corrosive, due to liberation of hydrochloric acid in presence of moisture. It is extremely irritating to the eyes, lungs, a n d mucous membranes. Workers should he protected from its mines by adequate ventilation and warned to keep it away from their hands. Sulphuric Acid 171. A strongly corrosive, dense, oily liquid, colorless to dark brown, depending upon its purity. Used for removing cotton fiber in reclaiming old rubber. In a diluted form it is used as a coagulant for latex mix- tures It is also used in attaching rubber to metals and in producing suiphonated rubber resin products. It causes vet v severe burns and will char almost any organic matter. Workers using sulphuric acid should he protected from having the mate- rial fly their eves or Onto their skin in even their clothing. The acid will iapiak, eat it s way through clothing to the flesh. (See N.S.C. pamphlet No. 23, "Acids and Caustics." for details.) Au Toluene :72. A colorless flammable liquid obtained by bactional distillation of caal-tar oil It resembles benzine in odor many of its properties, al- though it is less volatile at room raperto ores. I t is an excellent rub- tier solvent, used for rubber cements, dough, and as a cleansing solution. It is toxic and should be treated in the same intoner as benzol. Poisoning enucts can be very serious. Workers should be protected from its vapors and should keep it front their hands. Its vapors are heavy and cling to the boor and in poorly ventilated corners. (Sec benzol for handling.) Turpentine 173. Also called spirits Of turpentine. A clear, flammable,Colorless liquid with a characteristic rosinlike odor, obtained by distillation from turpentine rosin. Turpentine is a powerful solvent for rubber and was formerly used in making rubber cements. lint its use in rubber work has become very limited, and it is no longer an important factor in rubber manufacturing. It is toxic and irritating to the skin, eyes and respiratory organs. (See N.S.C. Industrial Data Sheet D-Chem. 12, "Turpentine" for details.) Xylene or Xylol 174. Xylene is a clear, colorless, flammable liquid with a characteristic penetrating odor. It is one of the constituents of mil-tar naphtha and is obtained from the latter source by distillation. It is: a good solvent for rubber and is nsetl in rubber cements, (loughs for the spreading trade, and as a swabbing solution in the manufacture of rubber goods. It is toxic, but not to so great an extent as benzol and toluene, probably because it is less volatile. It is a lire hazard, and the same precautions should be taken bath for lire and toxicity as those noted for benzol. Gases 175. Comparatively few gases are used in rubber manufacture, and in nearly every case they are used for vulcanization in some form. Gases are handled in closed chambers. Consequently, leakage or inadequate exhaust systems are the usual causes of trouble or discomfolt to the workers. Ammonia Gas 176. A colorless gas with a powerlul, penetiating and irritating odor. It affects the eves and respiratory organs. it is used for neutralizing any acid after sulphur chloride v apor cures, It is produced by heating concenti tiled liquid ammonia water in the curing chamber and ilnally is exhausted by suction or forced air. (For full details see N.S.C. pamphlets No. 25, "Acids and Citttics," and No. 93, "Safe Handling of Compressed Gases.") Chlorine Gas 177. A heavy, greenish-yellow gas. highly irritating and toxic. It is used only in specialized industries; for instance, in producing chlorinated lubber. It must he rigidly confined in suitable chambers and kept away from workers. It is extremely corrosive, therefore hazardous, esi,eciall in the presence of moisture. t For further data on chlorine sec N S.C. pamphlet No. 71, "Safe Handling of Chlorine.") hydrogen Chloride 178, Also known as hydrochloric acid gas; is colorless and exceedingly pungent. It is highly irritating and toxic. It has a strong affinity for water and should In' kept in closed systems. It is used only in special-, ized industries where ruble' is converted into certain resinous products. It requires special handling. Ilydrogen Sulphide 179. A colorless, flanimahle guts, with a very offensive odor and a sweetish taste. It is used only to a limited extent for specialized work in vulcanization of sheet or spread goods in conjunction with other re active gase-. It is highly toxic anal flammable and must be handled with great care. The go.ids are exposed in closed chambers and the gas blown in and hitt r expelled. (For details On it-, health hazards see N.S.0 Industrial Data Sheet No 16, 'I vdrogen Sulphide.") Sulphur Chloride 150. (See sulphur chloride taidc, liquids.) Where the gas is used it is merely the liquid sulphur chloride vaporized by heat ii-. the hot curing chambers for vapor curing of sheet and spread goods I,,saally Ilse ;good; ale festooned in large room, or chambers, and ,t quantity of nqual sulphur chloride is evaporated on a hot plate, circulation being accomiilished by fan it necessary. Concentrations ate usually small, and therefore serious hazard is avolded with adequate ventilation. Sulphur Dioxide 181. A poisonous, coli:riess with a suffocating odor, It i, usfr 11 IN1)USTRI:11,,SAIET1' SERIES NO. RU-3 ,,,p,k1 in special industries for producrug special types of vulcanized products. The vulcanization must be carried out in closed chambers, and workers should be adequately protected from the gas. :ICK,V0111.EDGMENT This pamphlet is based on a paper presented before the Rubber Section of the National Safety Couruil by L. J. D. Healy, consulting chemist, Milwaukee, Wisconsin. The National Safely Council is indebted to .11r. Healy and the Executive Committee of the Rubber Section, under whose direction flu pamphlet was published. 10-38-3M.